The dynamic surface tension of various proteins, including serum albumin and the serum lipoproteins, are being measured by means of the pendent drop metod. Interpretation in terms of the Gibb's adsorption isotherm and a suitable equation of state for the protein film will be made in order to deterine the surface orientation of the proteins. The kinetics of the bindngof fatty acid anions by serum albumin will be studied wth a stop-flow systemlinked to a dielectric probe after mixing the chamber. Since we have an independent evaluation of the change in dielectric incremet of the albumin as a function of the amount of fatty acid bound, we can evaluate the rate of binding if the time constants are larger than about l msec. Investigations on three human plasma proteins; alpha 1T-glycoprotein (tryptophan-poor protein), alpha 1-antitrypsin and antithrombin (heparin coactor) have been initiated. If we succeed in sufficient purification of these cmponents, physical-chemical and biophyscal properties will be evaluate. Osmotic pressure of non-ionic surfactants in mixtures with serum albumin wll also be evaluated.